Any scanning/ barcode app that allowes you to type in UPC code?

I see 3 to 4 apps that can scan a barcode and get the info. But I am looking for an app where I can type in the UPC code and get the info/ price / price comparison. Why is it hard to find such an app? Is there a website where I can type in online and find the info for the UPC code. Please advice. I also had a situation yesterday where the UPC code is too small for the barcode scanner or shopsavvy app to scan. typing in the UPC code is the only way in that cases. Please help to find an app like that. (also a website)
Thanks in advance